A 19-year old female who was transplanted (father donor) 2 years back. Native kidney disease unknown. Pre-transplant ANA negative. Urine R- 2+ protein, no RBCs. No episodes of hematuria prior to transplant. She was treated with triple immunosuppression (Tac, MMF, Steroid). One episode of CMV disease a few months after transplant treated with valganciclovir. Subsequently she has been stable with S. Cr 1.0 mg/dl. Multiple post-tx urine routine negative for blood and protein. 4 weeks back she developed transient hematuria and upper resp tract infection. Hematura recurred 2 weeks later. S. Cr. was 1.1 mg/dl. Another week later she developed edema and hematuria recurred. S. Cr had increased to 1.8. Admitted for further evaluation. Ultrasound of kidneys WNL. Repeat S. Cr 1.6 –> 1.8 next day. Transplant biopsy done. Suspecting BKV nephropathy vs. Rejection vs. glomerulonephritis. Biopsy report showed crescentic GN strongly positive for anti-GBM staining – 5 of 7 gloms showing active cellular crescents. No scarring. mild tubular damage. C4d negative. ASO, C3, C4, all normal. ANA positive 1:40 speckled (Rheumatologist opines this as non-significant) S. Cr incresed to 2.2 mg/dl. Pulse steroids (500 mg x 3) + plasma exchange initiated (5 cycles completed). S. Cr now 1.8 and macroscopic hematuria has cleared. Anti-GBM and ANCA titers pending. Current immunosuppressive medications: Oral Prednsone increased to 1 mg/kg (50 mg/day) MMF increased to 500 mg tid (from bid) Tacrolimus remains at 1.5 mg bd (trough level 7.3) Need your advise on further care. ? Cyclophosphamide – dose and duration ? Rituximab – dose and duration